微信公众号搜"智元新知"关注
微信扫一扫可直接关注哦!

AngularJS承诺数组

任何人都可以帮我一些Angular的承诺吗?我有以下函数应该接受一个文件对象数组,迭代它们,并上传一个.在每次迭代期间,promise对象被推送到promises数组.在我的上传函数中,我有一个附加.then()的循环函数,在所有promise对象都已解析之前不应该调用它.我认为我的代码看起来是正确的,但它无法正常工作.图像上传,但是立即调用循环(文件).then(),而不是一旦promises数组结算.

function upload(files) {
    var uploadCount = files.length;
    function cycle(files) {
        var promises = [];
        for (var i = 0; i < files.length; i++) {
            var deferred = $q.defer();
            promises.push(deferred);
            var file = files[i];
            Upload.upload({
                url: '/photos.json',file: file
            }).success(function(){
                $scope.progressCurrentCount += 1;
                deferred.resolve();
            });
        };
        return $q.all(promises);
    };

    cycle(files).then(function(result) {
        if(uploadCount > 1) {
            $scope.lastAction = 'uploaded ' + uploadCount + ' photos';
        } else {
            $scope.lastAction = 'uploaded ' + uploadCount + ' photo';
        }
        $scope.showSuccessModal = true;
        $scope.uploading = false;
        $scope.FailedUploads = [];
        $scope.newPhotos = {
            token: $scope.token,files: undefined
        };
        photoUploadBtn.removeClass('disabled');
    })
};

最终工作代码*

而不是设置var deferred = $q.defer();将deferred.promise推入promises数组,然后在我的.success()回调中解析延迟,这不起作用,我只是将我的Upload.upload()函数推送到promises中而没有.success()回调,然后传递到$q.all(),它完成所有提升.

function upload(files) {
    var uploadCount = files.length;
    function cycle(files) {
        var promises = [];
        for (var i = 0; i < files.length; i++) {
            var file = files[i];
            var promise = Upload.upload({
                url: '/photos.json',file: file
            });
            promises.push(promise);
        };
        return $q.all(promises);
    };

    cycle(files).then(function(result) {
        if(uploadCount > 1) {
            $scope.lastAction = 'uploaded ' + uploadCount + ' photos';
        } else {
            $scope.lastAction = 'uploaded ' + uploadCount + ' photo';
        };
        $scope.showSuccessModal = true;
        $scope.uploading = false;
        $scope.FailedUploads = [];
        $scope.newPhotos = {
            token: $scope.token,files: undefined
        };
        photoUploadBtn.removeClass('disabled');
        getPhotos(q);
    })
};

解决方法

你必须将promise,而不是deferred,推送到promises数组:

promises.push(deferred.promise);

如果您这样考虑它会有所帮助:

> promise是您想要返回给消费者的只读对象> deferred是该只读承诺的修饰符,您希望自己保留它

版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 [email protected] 举报,一经查实,本站将立刻删除。

相关推荐